Synthesis, Structure And Properties Researches Of Extended Structure Constructed From Sandwich-type Polyoxotungstate

The design and synthesis of high-nuclear compounds have been the focus inpolyoxometalate chemistry. What is more, the design and synthesis of TM-substituted POMshave been aroused broad interest, as they exhibit a variety of structural features and propertiesincluding catalysis, magnetism and photochemistry.In this paper, we make use of theconventional aqueous solution methods and hydrothermal technique to obtain extendedstructure constructed from sandwich-type polyoxotungstates, then we discussed synthetic ruleand condition for these new compounds. We also investigate the structures and proerties ofthese compounds. Extended structures constructed from sandwich-type polyoxotungstateswere characterized by elemental analyses, electrochemistry, IR, TG, UV-vis and single crystalX-ray diffractions.In the conventional aqueous solution condition, we synthesized a novel polyoxotungstate{Na₆（H₂O）₁₆}[{Mn₃（H₂O）₆W（OH）₂}{SbW₉O₃₃}₂]·13H₂O （1）. Compound1exhibits a1-Dchain-like structure composed of the sandwich-type tungstoantimonites fused together bywater substitution on the sandwiching metal centers, which was rarely observed in the POMchemistry.In the hydrothermal technique, we obtained two new compounds constructed frommixture-valence {Fe6}-cluster-containing sandwich-type tungstoferrates （H₂enMe）₅{Fe₂^IIIFe₂^II（HenMe）₂[B-α-FeW₉O₃₄]₂}·12H₂O （2） and （H₂enMe）₃Fe_II（enMe）₂H₂{Fe₂^IIIFe₂^II（HenMe）₂[B-α-Fe^IIIW₉O₃₄]₂}·13H₂O （3）（enMe=1,2-diaminopropane）. Compound1is an isolated{Fe6}-cluster-containing sandwich-type tungstoferrate functionalized by two enMe ligands.Compound2exhibits a1-D chain-like structure composed of the sandwich-typepolyoxoanions linked by iron linkers via the bridging oxygen atoms, representing the firstextended structure based on tungstoferrates.